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The contamination of soils by metals such as arsenic, chromium, copper and organic compounds such as pentachlorophenol (PCP) and dioxins and furans (PCDD/F) is a major problem in industrialized countries. Excavation followed by disposal in an appropriate landfilling is usually used site to manage these contaminated soils. Many researches have been conducted to develop physical, biological, thermal and chemical methods to allow the rehabilitation of contaminated sites. Thermal treatments including thermal desorption seemed to be the most appropriate methods, allowing the removal of more than 99.99% of organic contaminants but, they are ineffective for inorganic compounds. Biological treatments have been developed to remove inorganic and hydrophobic organic contaminants but their applications are limited to soils contaminated by easily biodegradable organic compounds. Among the physical technologies available, attrition is the most commonly used technique for the rehabilitation of soils contaminated by both organic and inorganic contaminants. Chemical processes using acids, bases, redox agents and surfactants seemed to be an interesting option to simultaneously extract organic and inorganic contaminants from soils. This paper will provide an overview of the recent developments in the field of decontamination technologies applicable for the removal of As, Cr, Cu, PCP and/or PCDD/F from contaminated soils., (Copyright © 2017 Elsevier B.V. All rights reserved.)

The objective of this study was to evaluate at the pilot scale the performance of a chemical leaching process for Pb, Cu, Sb, and Zn removal from a fine fraction () of soil at two Canadian small-arms shooting ranges (SASR; Batoche: , , , and ; Normandie: , , , and ). A comparison of different leaching reagents revealed that the use of (4 M) is a very promising option from an economic point of view to solubilize metallic pollutants from highly polluted soils. The results showed that chemical treatment, including three successive acid-leaching steps (, , , ) followed by one rinsing step using water [pulp density , time , temperature ], resulted in metal removal yields of 93% Cu, 97% Pb, 89% Sb, and 70% Zn in Batoche soil and 85% Cu, 96% Pb, 59% Sb, and 49% Zn in Normandie soil. Subsequently, Sb and other dissolved metals (Cu, Pb, and Zn) were successfully recovered via chemical precipitation/coprecipitation (99.1% Cu, Pb, 95.1% Sb, and 99.9% Zn-Batoche; 90.4% Cu, Pb, 79.1% Sb, and ) by adding NaOH until . [ABSTRACT FROM AUTHOR]